• May 1, 2024
• in Linux
• 1 min read

Process Management in Linux

Introduction

In Linux, a process is simply a program that is currently running. When you execute a command, it starts a process.

1. Processes can be categorized into Foreground Processes, which require user input and run in the foreground.
2. Background processes, which run independently of the user.

Understanding processes is essential for managing and interacting with programs effectively in Linux.

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Process States

A process state refers to the current condition or status of a process in its execution lifecycle

graph TD;
    A[Created] --> B[Running]
    B --> C[Sleeping]
    C --> D[Interruptible sleep]
    C --> E[Uninterruptible sleep]
    B --> F[Stopped]
    F --> G[Zombie]

Describing various attributes of a process:

Attribute	Description
PID	Unique Process ID given to each process.
User	Username of the process owner.
PR	Priority given to a process while scheduling.
NI	'nice' value of a process.
VIRT	Amount of virtual memory used by a process.
RES	Amount of physical memory used by a process.
SHR	Amount of memory shared with other processes.
S	State of the process: 'D' = uninterruptible sleep, 'R' = running, 'S' = sleeping, 'T' = traced or stopped, 'Z' = zombie.
%CPU	Percentage of CPU used by the process.
%MEM	Percentage of RAM used by the process.
TIME+	Total CPU time consumed by the process.
Command	Command used to activate the process.

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